JP6060921B2 - Slag continuous casting equipment - Google Patents

Description

  The present invention relates to an apparatus for continuously casting molten slag generated in a steel making process.

  In recent years, as shown in FIG. 2, after melting and solidifying molten steelmaking slag (molten slag), roughly crushing, crushing and adjusting the particle size to obtain granular solidified slag (granular slag), Steel slag hydrated solidified technology that kneads with binder (blast furnace slag fine powder, cement, etc.) and water, places and cures, coarsely crushes, and classifies to produce lump (rock-like) artificial stone (See Non-Patent Document 1) has begun to spread.

  In this way, by using molten slag as artificial stone (bulk slag), it is used for marine civil engineering, and has better results for bioadhesiveness such as seaweed than concrete.

  However, conventionally, when manufacturing an artificial stone from molten slag, as shown in FIG. 1, many processes are required. Therefore, if the molten slag can be cast and solidified directly into a lump, the rough crushing step, crushing / particle size adjusting step, kneading step, placing / curing step, and rough crushing step in FIG. 1 can be omitted, which is efficient. Here, the massive slag is, for example, one having an equivalent diameter of about 100 mm to 500 mm when the spheres have the same volume.

  However, a method for stably casting molten slag directly into a lump has not been put to practical use.

  For example, as a method of directly solidifying molten slag, a twin roll type continuous solidification method in which molten slag is introduced between twin rolls and continuously formed into a plate shape and cooled and solidified is performed (for example, Patent Documents 1 to 3).

  However, since the thermal conductivity of the steelmaking slag is small, it takes a long time of 24 hours or more to solidify into a lump. As in Patent Documents 1 to 3, in the continuous solidification method using the twin roll method, the time for which the molten slag contacts the twin roll is as short as several seconds, and only a plate-like slag (plate-like slag) having a thickness of about 4 mm can be produced.

  Moreover, although it is not a system which solidifies continuously, as a method of producing a large solidified slag, in Patent Document 4, as a solidification system of an electric furnace slag, molten slag is poured into a mold, and the thickness of the slag is 10 mm to 300 mm. A method of coagulating is disclosed.

  However, as in Patent Document 4, when molten slag is poured into a mold and solidified into a lump, the cooling rate between the surface and the inside becomes large, so if it is held on the mold for a long time, it depends on the temperature difference between the surface and the inside of the slag. Thermal stress cracking occurs, and a massive slag having a desired size cannot be stably produced.

JP 2003-137617 A JP 2004-28416 A JP 2004-26548 A JP 2008-121958 A

Iron and Steel Slag Hydrated Solids Technical Manual (Revised), Coastal Technology Research Center, February 2008

  This invention is made | formed in view of the above situations, and it aims at providing the slag continuous casting apparatus which can cast and solidify the molten steelmaking slag in the lump shape efficiently and stably. Is.

  In order to solve the above problems, the present invention has the following features.

  [1] A slag continuous casting apparatus that continuously casts and solidifies molten slag generated in a steelmaking process between molds, and a pair of endless track molds arranged opposite to each other, A slag pan for supplying molten slag between the endless track molds, a cutting device for cutting the semi-solid slag extracted from between the pair of endless track molds into a lump, and after cutting by the cutting device A slag continuous casting apparatus comprising: a holding container for gradually cooling the lump-shaped semi-solid slag.

  [2] The mold is driven by connecting a plurality of divided molds having a thin mold thickness part and a thick mold thickness part, and the thick mold parts face each other to form a semi-solid slag. The slag continuous casting apparatus according to [1], wherein the thinned portion is cut by the cutting device.

  [3] The slag continuous casting apparatus according to [1] or [2], further including an air nozzle that blows air onto the molten slag supplied from the slag pan.

  In the present invention, the molten steelmaking slag can be cast and solidified into a lump efficiently and stably.

It is a figure which shows the slag continuous casting apparatus in one Embodiment of this invention. It is a figure which shows the manufacturing process of an artificial stone.

  An embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a view showing a slag continuous casting apparatus (slag continuous solidification apparatus) in one embodiment of the present invention.

  As shown in FIG. 1, a slag continuous casting apparatus 10 according to an embodiment of the present invention includes a pair of endless track type (caterpillar type) molds 11 arranged opposite to each other, and this endless track type mold (hereinafter simply referred to as “ A cooling device 12 that sprinkles and cools the mold 11), a slag pan 13 and a tilting device 14 that supply molten slag 21 at a constant flow rate between the pair of molds 11, and the slag pan 13. The air nozzle 15 that blows air to the molten slag 21, the cutting device 16 that cuts the semi-solid slag 22 extracted from between the pair of molds 11 into a lump, and the lump-shaped semi-solid slag after being cut by the cutting device 16 A conveyor 17 that receives and conveys the slag 23, and a holding container 18 that stores the massive semi-solid slag 23 conveyed by the conveyor 17 and gradually cools it until it becomes a massive solidified slag (artificial stone) 24. To have.

  In the pair of endless track type molds 11 arranged opposite to each other, a plurality of divided molds 11A having a flat part 11a having a thin mold thickness and a convex part 11b having a thick mold thickness are connected and driven. Thus, the thickness of the semi-solid slag 22 is increased in the flat portion 11a to form the thick portion 22a, and the thickness of the semi-solid slag 22 is decreased in the convex portion 11b to form the thin portion 22b. . The material of the divided mold 11A is preferably made of cast steel.

  In the slag continuous casting apparatus 10 configured as described above, a pair of molds 11 driven by an endless track type are disposed oppositely to continuously solidify the molten slag 21 supplied between the molds 11. can do. And by connecting the some division | segmentation mold 11A provided with the flat part 11a and the convex part 11b, while the flat part 11a hold | maintains the molten slag 21 and solidifies in a lump, the convex part 11b melt | dissolves the molten slag 21. Will solidify quickly.

  Moreover, by providing the tilting device 14 in the slag pan 13, the molten slag 21 can be supplied at a constant flow rate. In addition, since the slag continuous casting apparatus 10 itself will also become large if the flow volume of the molten slag 21 to supply becomes large too, it is desirable for the flow volume of the molten slag 21 to supply to be about 1-2 t / min.

In addition, by providing an air nozzle 15 that blows air to the molten slag 21 supplied from the slag pan 13, the FeO in the molten slag 21 is oxidized to Fe ₂ O ₃ , whereby 2CaO · Fe ₂ O ₃ is converted to Fe ₂ O ₃ . The free CaO in the massive slag 24 after being generated and solidified can be reduced to 1% by mass or less. As a result, the hydrated expansion of the massive slag 24 can be suppressed. Further, by blowing air to the molten slag 21 supplied between the pair of molds 11, the temperature of the molten slag 21 is lowered, and the time for cooling between the molds 11 can be shortened.

  Moreover, by providing the cutting device 16 on the outlet side of the mold 11, the thin portion 22b that is solidified but not yet hard can be cut. Thereby, the lump-like semi-solid slag 23 can be taken out from the mold 11 in a semi-molten state where the surface is solidified and the inside is unsolidified.

  When the bulk semi-solid slag 23 taken out from the mold 11 is transported to the holding container 18 by the conveyor 17, the semi-solid slag 23 is at a high temperature of 1000 ° C. or higher. Make something.

  Then, by storing the massive semi-solid slag 23 conveyed by the conveyor 17 in the holding container 18, the high-temperature massive semi-solid slag 23 is gradually cooled to obtain the massive solidified slag (artificial stone) 24. be able to. That is, in the holding container 18, the temperature difference between the surface and the inside of the semi-solid slag 23 is eliminated by the heat held by the massive semi-solid slag 23 itself, and the temperature in the holding container 18 is also maintained at a high temperature. The thermal stress cracking due to the temperature difference between the surface and the inside of the solidified slag 24 is suppressed, and a solidified slag (artificial stone) 24 having a desired size can be manufactured. For example, when the spheres have the same volume, the equivalent diameter is about 100 mm to 500 mm.

  Thus, in this embodiment, the molten steelmaking slag can be cast and solidified into a lump efficiently and stably.

  In order to confirm the effect of the present invention, massive solidified slag (artificial stone) 24 was produced from the molten slag 21 based on the embodiment of the present invention (slag continuous casting apparatus 10).

  At that time, the material of the endless track mold 11 (divided mold 11A) was made of cast steel, and the length of one divided mold 11A was 300 mm. The mold thickness of the flat part 11a was 50 mm, the mold thickness of the convex part 11b was 120 mm, and the distance between the opposing convex parts 11b was 20 mm.

  Then, converter decarburized slag (molten slag) 21 in a molten state at 1400 ° C. to 1500 ° C. was supplied between the endless track mold 11 at 1 to 2 ton / min.

  The molten slag 21 supplied between the molds 11 was cooled between the molds 11 for 2 minutes and solidified from the contact surface with the mold 11.

  And the thin part 22b of the semi-molten slag 22 extracted from the lower part of the casting_mold | template 11 was cut | disconnected by the cutting device 16, and the lump-like semi-molten slag 23 was obtained. At that time, the molten slag did not flow out from the cut portion.

  The obtained massive semi-molten slag 23 has a hexagonal column shape with a cross section of 300 mm square, but when it falls onto the stainless steel conveyor 17, only about 10 mm of the surface is solidified, An unsolidified portion remained inside. The semi-solid slag 23 was transported by a stainless steel conveyor 17 and stored in a holding container 18.

  This holding container 18 does not have a heating device or the like, and is a container that only houses the semi-molten slag 23. When the semi-solid slag 23 of about 10 t was accommodated and the lid was closed and held, the temperature in the holding container 18 increased to about 900 ° C., and then gradually decreased.

  The lump solidified slag (artificial stone) 24 obtained after cooling slowly to room temperature was of good quality without thermal stress cracking or the like.

DESCRIPTION OF SYMBOLS 10 Slag continuous casting apparatus 11 Endless track type mold 11A Divided mold 11a Flat part of divided mold 11b Convex part of divided mold 12 Cooling device 13 Slag pan 14 Tilt device 15 Air nozzle 16 Cutting device 17 Conveyor 18 Holding container 21 Molten slag 22 Cutting Previous semi-solid slag 22a Thick part of semi-solid slag 22b Thin part of semi-solid slag 23 Bulk semi-solid slag 24 Bulk solid slag (artificial stone)

Claims (3)

A slag continuous casting apparatus that continuously casts and solidifies molten slag generated in a steelmaking process between molds, and a pair of endless track molds arranged opposite to each other, and the pair of endless track types A slag pan for supplying molten slag between the molds, a cutting device for cutting the semi-solid slag extracted between the pair of endless track molds into a lump, and a lump shape after being cut by the cutting device A holding container for gradually cooling the semi-solidified slag ,
The slag continuous casting apparatus , wherein the mold includes a thin mold part and a thick mold part .   The mold is driven by connecting a plurality of divided molds having a thin mold part and a thick mold part. The thick mold parts face each other and the semi-solid slag is thin. The slag continuous casting apparatus according to claim 1, wherein the formed portion is cut by the cutting device.   The slag continuous casting apparatus according to claim 1, further comprising an air nozzle that blows air onto the molten slag supplied from the slag pan.

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